A major challenge facing an advancing electronics industry is high power dissipation that results in undesirable heating of electronic devices and unsatisfactory battery drain in portable electronic devices such as smartphones. Spin transport electronics (spintronics) is a relatively new field of electronics that offers advantages over traditional electronics in power dissipation, non-volatility, and speed. These advantages exist because spintronics convey information by electron spin instead of the charge magnitude that is used to convey information in traditional electronics.
Key processes used to convey information through spintronic devices include spin injection, spin transport, and spin switching. Spin injection generates a common spin polarization for a group of electrons and injects the spin polarized group of electrons into a spin transport layer to input a magnetic data bit. Spin transport occurs as the spin polarized group of electrons propagates through the spin transport layer that is made of an electrically conductive material. Spin switching occurs when the spin polarized group of electrons arrives at a detector that writes the spin polarization of the spin polarized group of electrons into a magnetization state of an output magnetic data bit.
The effectiveness of these key processes is in spin accumulation and spin current magnitude. A tunnel barrier layer made of a tunnel barrier material that is spin injection efficient is critical for realizing improved spin injection. Therefore, what is needed is an improved tunnel barrier-based spin injector having a tunnel barrier layer made of a tunnel barrier material that has greater spin injection efficiency than traditional tunnel barrier materials such as magnesium oxide (MgO).